Notice I'm only focussing on US foreign policies, non internal...

Notice I'm only focussing on US foreign policies, non internal domestic affair. Since you think 20 years is too short a look back period, we can go back to the slave trade then fast forward to the sixties, Martin Luther King, FBI outright spying on him, segregation, Juneteenth and so forth. I hope you realise that a lot of Nazis magically continued their career in the land of the free after WW2.

Then there is Korea, Vietnam, Laos, Cambodia, Nicaragua, Cuba an so forth. I'll stop here, just too many examples and I think you get the point.